| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.44 | 1.73 | 1.27 |
| 2024 | 1.23 | 1.71 | 0.75 |
| 2023 | 0.79 | 1.16 | 0.61 |
| 2022 | 0.66 | 1.04 | 0.54 |
| 2021 | 0.55 | 0.79 | 0.45 |
| 2020 | 0.63 | 0.91 | 0.46 |
| 2019 | 0.46 | 0.59 | 0.3 |
| 2018 | 0.36 | 0.5 | 0.22 |
| 2017 | 0.72 | 1.05 | 0.48 |
| 2016 | 0.91 | 1.05 | 0.74 |
| 2015 | 0.85 | 1.21 | 0.56 |
| 2014 | 0.82 | 1.03 | 0.63 |
| 2013 | 0.7 | 0.91 | 0.57 |
| 2012 | 0.68 | 0.84 | 0.57 |
| 2011 | 1.02 | 1.41 | 0.63 |
| 2010 | 0.99 | 1.32 | 0.71 |
| 2009 | 0.96 | 1.55 | 0.46 |
| 2008 | 0.58 | 0.98 | 0.29 |
| 2007 | 0.68 | 0.94 | 0.45 |
| 2006 | 0.42 | 0.55 | 0.35 |
| 2005 | 0.28 | 0.39 | 0.13 |
| 2004 | 0.23 | 0.37 | 0.13 |